import Vue from 'vue';
import {mergeRecursive} from '@/utils/common';
import DictMeta from './DictMeta';
import DictData from './DictData';

const VueApp: any = Vue;

const DEFAULT_DICT_OPTIONS = {
	types: [],
};

/**
 * @classdesc 字典
 *
 * @property {Object} label 标签对象，内部属性名为字典类型名称
 * @property {Object} dict 字段数组，内部属性名为字典类型名称
 * @property {Array.<DictMeta>} _dictMetas 字典元数据数组
 */
export default class Dict {
	owner: undefined;
	label: Record<string, unknown>;
	type: Record<string, unknown>;
	_dictMetas: any;
	constructor() {
		this.owner = undefined;
		this.label = {};
		this.type = {};
	}

	async init(options: {[x: string]: any; types?: any[]}) {
		if (options instanceof Array) {
			options = {types: options};
		}

		const opts = mergeRecursive(DEFAULT_DICT_OPTIONS, options);
		if (opts.types === undefined) {
			throw new Error('need dict types');
		}

		const ps: any[] = [];
		this._dictMetas = opts.types.map((t: any) => DictMeta.parse(t));
		this._dictMetas.forEach((dictMeta: {type: any; lazy: any}) => {
			const {type} = dictMeta;
			VueApp.set(this.label, type, {});
			VueApp.set(this.type, type, []);
			if (dictMeta.lazy) {
				return;
			}

			ps.push(loadDict(this, dictMeta));
		});
		return Promise.all(ps);
	}

	/**
	 * 重新加载字典
	 * @param {String} type 字典类型
	 */
	async reloadDict(type: any) {
		const dictMeta = this._dictMetas.find((e: {type: any}) => e.type === type);
		if (dictMeta === undefined) {
			return Promise.reject(`the dict meta of ${type} was not found`);
		}

		return loadDict(this, dictMeta);
	}
}

/**
 * 加载字典
 *
 * @param {Dict} dict 字典
 * @param {DictMeta} dictMeta 字典元数据
 * @returns {Promise}
 */
export const loadDict = async (dict: any, dictMeta: {type: any; lazy?: any; request?: any; responseConverter?: any}) => await dictMeta.request(dictMeta).then((response: any) => {
	const {type} = dictMeta;
	let dicts = dictMeta.responseConverter(response, dictMeta);
	if (!(dicts instanceof Array)) {
		console.error(
			'the return of responseConverter must be Array.<DictData>',
		);
		dicts = [];
	} else if (
		dicts.filter(d => d instanceof DictData).length !== dicts.length
	) {
		console.error('the type of elements in dicts must be DictData');
		dicts = [];
	}

	dict.type[type].splice(0, Number.MAX_SAFE_INTEGER, ...dicts);
	dicts.forEach((d: {value: any; label: any}) => {
		VueApp.set(dict.label[type], d.value, d.label);
	});
	return dicts;
});
